The purpose of this study is to explore the safety, tolerability, pharmacokinetics, immunogenicity and preliminary efficacy of INCB024360 administered in combination with MEDI4736 in subjects with selected advanced solid tumors.

This is a study using pembrolizumab (MK-3475, KEYTRUDA®) for first-line treatment of participants with advanced/unresectable (inoperable) or metastatic urothelial cancer who are ineligible for cisplatin-based therapy. The primary study objective is to determine the objective response rate (ORR) in all participants, in participants whose tumors rely on programmed cell death ligand 1 (PD-L1) protein (PD-L1-positive tumors), and in participants with strongly PD-L1-positive tumors.